http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
effects of kisspeptin-54 on reproductive functions in paraquat-exposed adult male and female rats
xxvi, 237 leaves : some colour illustrations ; 30 cm.
Kisspeptin (KP) has been recognized as a crucial regulator of the onset of puberty, the regulation of sex hormone-mediated secretion of gonadotrophins, and the control of fertility. Thus, the present study was aimed to investigate the potential roles of KP-S4 in modulating the reproductive adverse effects caused by Paraquat (PQ) exposure in rats. A total of SO male and SO female adult Sprague-Dawley rats were used in the present study. Rats were randomly divided into two groups; (i) PQ (n= 40) and (ii) normal saline, PQ- (n= 10) for a period of 30 days. All PQ treated rats were given 13mg/kg of PQ intraperitoneal for 30days (LDso for femaJe rat j 26mgi/kg; i .. ) and l2.Smg/kg of PQ in male rats (LDso for male rat i 2Smg/kg). The rats that received intraperitoneal PQ were further divided into four groups (n= 10 per group) (i) untreated PQ-exposed (PQ+) (ii) PQ-exposed rats treated with low dose of KP-S4 (PQ/KP low; 1 pg/kg) (iii) PQ-exposed rats treated with interm diate dose of KP-S4 (PQ/KP intermediate; lng/kg) (iv) PQ-exposed rats treated with high dose of KP-S4 (PQ/KP high; 1 ug/kg). Male rats were sacrificed after seven days of KP-S4 treatment. Serum was used for hormonal assays i.e. FSH, LH, PRL, inhibin B, testosterone and tissues were subjected for histopathology, and testicular tissues were subjected for measurement of enzymes and oxidative markers, and the epididymis sperms were used for sperm assays. For female rats, daily vagina smear was conducted for 32 days starting from Day 1 KP-S4 treatment. After sacrifice, the serum was used for hormonal assays i.e. FSH, LH, PRL, inhibin B, estradiol and progesterone, and tissues were subjected for histopathology and pregnancy outcome, and ovarian tissues were subjected for measurement of oxidative markers. In the present study, both male and female reproductive functions were affected by subchronic PQ exposure. Findings from the present study confirmed the adverse effects of PQ leading to reduced reproductive organs weight, altered morphological appearances of reproductive organs through germinal epithelium sloughing and increased degenerating cells as well as their quantitative parameters, increased malonylaldehyde (MDA) and superoxide dismutase (SOD) levels in testicular and ovarian tissues, increased testicular phosphatase (ACP) and sorbitol dehydrogenase (SOH), reduced sperm quality and ovum numbers. Pituitary and gonadal hormonal levels were also reduced following PQ exposure and these could contribute to testicular and ovarian dysfunctions. Continuous intraperitoneal injection of KP-S4 for seven days failed to reverse the PQ-induced reproductive dysfunctions except for sperm motility. KP-54 treatment exerted further negative effects on reproductive functions of both male and female rats. In conclusion, the present study demonstrated that subchronic PQ expo ure caused adverse effects on fertility and reproduction of adult male and female rats and continuous intraperitoneal injection of KP-S4 for seven days not only failed to reverse the adverse effects induced by subchronic PQ exposure but induced further adverse effects on fertility and reproduction of adult male and female rats.
Thesis (Degree of Doctor of Philosophy) - Universiti Sultan Zainal Abidin, 2016
Includes bibliographical references (pages 191-231)